1/*
2 * quick and dirty way to populate a /dev directory
3 *
4 * Copyright (C) 2004 Harald Hoyer <harald@redhat.com>
5 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
6 * Copyright (C) 2004-2006 Kay Sievers <kay@vrfy.org>
7 *
8 *	This program is free software; you can redistribute it and/or modify it
9 *	under the terms of the GNU General Public License as published by the
10 *	Free Software Foundation version 2 of the License.
11 *
12 *	This program is distributed in the hope that it will be useful, but
13 *	WITHOUT ANY WARRANTY; without even the implied warranty of
14 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 *	General Public License for more details.
16 *
17 *	You should have received a copy of the GNU General Public License along
18 *	with this program; if not, write to the Free Software Foundation, Inc.,
19 *	51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
20 *
21 */
22
23#include <stdlib.h>
24#include <stddef.h>
25#include <string.h>
26#include <stdio.h>
27#include <unistd.h>
28#include <errno.h>
29#include <ctype.h>
30#include <dirent.h>
31#include <signal.h>
32#include <syslog.h>
33#include <sys/wait.h>
34#include <sys/stat.h>
35#include <sys/types.h>
36
37#include "udev.h"
38#include "udev_rules.h"
39#include "udev_selinux.h"
40
41static const char *udev_run_str;
42static const char *udev_log_str;
43static struct udev_rules rules;
44
45#ifdef USE_LOG
46void log_message(int priority, const char *format, ...)
47{
48	va_list args;
49
50	if (priority > udev_log_priority)
51		return;
52
53	va_start(args, format);
54	vsyslog(priority, format, args);
55	va_end(args);
56}
57#endif
58
59struct device {
60	struct list_head node;
61	char path[PATH_SIZE];
62};
63
64/* sort files in lexical order */
65static int device_list_insert(const char *path, struct list_head *device_list)
66{
67	struct device *loop_device;
68	struct device *new_device;
69	const char *devpath = &path[strlen(sysfs_path)];
70
71	dbg("insert: '%s'", devpath);
72
73	list_for_each_entry(loop_device, device_list, node) {
74		if (strcmp(loop_device->path, devpath) > 0) {
75			break;
76		}
77	}
78
79	new_device = malloc(sizeof(struct device));
80	if (new_device == NULL) {
81		dbg("error malloc");
82		return -ENOMEM;
83	}
84
85	strlcpy(new_device->path, devpath, sizeof(new_device->path));
86	list_add_tail(&new_device->node, &loop_device->node);
87	dbg("add '%s'" , new_device->path);
88	return 0;
89}
90
91/* list of devices that we should run last due to any one of a number of reasons */
92static char *last_list[] = {
93	"/block/dm",	/* on here because dm wants to have the block devices around before it */
94	NULL,
95};
96
97/* list of devices that we should run first due to any one of a number of reasons */
98static char *first_list[] = {
99	"/class/mem",
100	"/class/tty",
101	NULL,
102};
103
104static int add_device(const char *devpath)
105{
106	struct sysfs_device *dev;
107	struct udevice *udev;
108	int retval = 0;
109
110	/* clear and set environment for next event */
111	clearenv();
112	setenv("ACTION", "add", 1);
113	setenv("UDEV_START", "1", 1);
114	if (udev_log_str)
115		setenv("UDEV_LOG", udev_log_str, 1);
116	if (udev_run_str)
117		setenv("UDEV_RUN", udev_run_str, 1);
118
119	dev = sysfs_device_get(devpath);
120	if (dev == NULL)
121		return -1;
122
123	udev = udev_device_init(NULL);
124	if (udev == NULL)
125		return -1;
126
127	/* override built-in sysfs device */
128	udev->dev = dev;
129	strcpy(udev->action, "add");
130
131	if (strcmp(udev->dev->subsystem, "net") != 0) {
132		udev->devt = udev_device_get_devt(udev);
133		if (major(udev->devt) == 0)
134			return -1;
135	}
136
137	dbg("add '%s'", udev->dev->devpath);
138	setenv("DEVPATH", udev->dev->devpath, 1);
139	setenv("SUBSYSTEM", udev->dev->subsystem, 1);
140
141	udev_rules_get_name(&rules, udev);
142	if (udev->ignore_device) {
143		dbg("device event will be ignored");
144		goto exit;
145	}
146	if (udev->name[0] != '\0')
147		retval = udev_device_event(&rules, udev);
148	else
149		info("device node creation supressed");
150
151	if (retval == 0 && udev_run) {
152		struct name_entry *name_loop;
153
154		dbg("executing run list");
155		list_for_each_entry(name_loop, &udev->run_list, node) {
156			if (strncmp(name_loop->name, "socket:", strlen("socket:")) == 0)
157				pass_env_to_socket(&name_loop->name[strlen("socket:")], udev->dev->devpath, "add");
158			else {
159				char program[PATH_SIZE];
160
161				strlcpy(program, name_loop->name, sizeof(program));
162				udev_rules_apply_format(udev, program, sizeof(program));
163				run_program(program, udev->dev->subsystem, NULL, 0, NULL, (udev_log_priority >= LOG_INFO));
164			}
165		}
166	}
167
168exit:
169	udev_device_cleanup(udev);
170	return 0;
171}
172
173static void exec_list(struct list_head *device_list)
174{
175	struct device *loop_device;
176	struct device *tmp_device;
177	int i;
178
179	/* handle the "first" type devices first */
180	list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
181		for (i = 0; first_list[i] != NULL; i++) {
182			if (strncmp(loop_device->path, first_list[i], strlen(first_list[i])) == 0) {
183				add_device(loop_device->path);
184				list_del(&loop_device->node);
185				free(loop_device);
186				break;
187			}
188		}
189	}
190
191	/* handle the devices we are allowed to, excluding the "last" type devices */
192	list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
193		int found = 0;
194		for (i = 0; last_list[i] != NULL; i++) {
195			if (strncmp(loop_device->path, last_list[i], strlen(last_list[i])) == 0) {
196				found = 1;
197				break;
198			}
199		}
200		if (found)
201			continue;
202
203		add_device(loop_device->path);
204		list_del(&loop_device->node);
205		free(loop_device);
206	}
207
208	/* handle the rest of the devices left over, if any */
209	list_for_each_entry_safe(loop_device, tmp_device, device_list, node) {
210		add_device(loop_device->path);
211		list_del(&loop_device->node);
212		free(loop_device);
213	}
214}
215
216static int has_devt(const char *path)
217{
218	char filename[PATH_SIZE];
219	struct stat statbuf;
220
221	snprintf(filename, sizeof(filename), "%s/dev", path);
222	filename[sizeof(filename)-1] = '\0';
223
224	if (stat(filename, &statbuf) == 0)
225		return 1;
226
227	return 0;
228}
229
230static void udev_scan_block(struct list_head *device_list)
231{
232	char base[PATH_SIZE];
233	DIR *dir;
234	struct dirent *dent;
235
236	snprintf(base, sizeof(base), "%s/block", sysfs_path);
237	base[sizeof(base)-1] = '\0';
238
239	dir = opendir(base);
240	if (dir != NULL) {
241		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
242			char dirname[PATH_SIZE];
243			DIR *dir2;
244			struct dirent *dent2;
245
246			if (dent->d_name[0] == '.')
247				continue;
248
249			snprintf(dirname, sizeof(dirname), "%s/%s", base, dent->d_name);
250			dirname[sizeof(dirname)-1] = '\0';
251			if (has_devt(dirname))
252				device_list_insert(dirname, device_list);
253			else
254				continue;
255
256			/* look for partitions */
257			dir2 = opendir(dirname);
258			if (dir2 != NULL) {
259				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
260					char dirname2[PATH_SIZE];
261
262					if (dent2->d_name[0] == '.')
263						continue;
264
265					snprintf(dirname2, sizeof(dirname2), "%s/%s", dirname, dent2->d_name);
266					dirname2[sizeof(dirname2)-1] = '\0';
267
268					if (has_devt(dirname2))
269						device_list_insert(dirname2, device_list);
270				}
271				closedir(dir2);
272			}
273		}
274		closedir(dir);
275	}
276}
277
278static void udev_scan_class(struct list_head *device_list)
279{
280	char base[PATH_SIZE];
281	DIR *dir;
282	struct dirent *dent;
283
284	snprintf(base, sizeof(base), "%s/class", sysfs_path);
285	base[sizeof(base)-1] = '\0';
286
287	dir = opendir(base);
288	if (dir != NULL) {
289		for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
290			char dirname[PATH_SIZE];
291			DIR *dir2;
292			struct dirent *dent2;
293
294			if (dent->d_name[0] == '.')
295				continue;
296
297			snprintf(dirname, sizeof(dirname), "%s/%s", base, dent->d_name);
298			dirname[sizeof(dirname)-1] = '\0';
299
300			dir2 = opendir(dirname);
301			if (dir2 != NULL) {
302				for (dent2 = readdir(dir2); dent2 != NULL; dent2 = readdir(dir2)) {
303					char dirname2[PATH_SIZE];
304
305					if (dent2->d_name[0] == '.')
306						continue;
307
308					snprintf(dirname2, sizeof(dirname2), "%s/%s", dirname, dent2->d_name);
309					dirname2[sizeof(dirname2)-1] = '\0';
310
311					if (has_devt(dirname2) || strcmp(dent->d_name, "net") == 0)
312						device_list_insert(dirname2, device_list);
313				}
314				closedir(dir2);
315			}
316		}
317		closedir(dir);
318	}
319}
320
321static void asmlinkage sig_handler(int signum)
322{
323	switch (signum) {
324		case SIGALRM:
325			exit(1);
326		case SIGINT:
327		case SIGTERM:
328			exit(20 + signum);
329	}
330}
331
332int main(int argc, char *argv[], char *envp[])
333{
334	LIST_HEAD(device_list);
335	struct sigaction act;
336
337	logging_init("udevstart");
338	udev_config_init();
339	selinux_init();
340	dbg("version %s", UDEV_VERSION);
341
342	udev_run_str = getenv("UDEV_RUN");
343	udev_log_str = getenv("UDEV_LOG");
344
345	/* disable all logging if not explicitely requested */
346	if (udev_log_str == NULL)
347		udev_log_priority = 0;
348
349	/* set signal handlers */
350	memset(&act, 0x00, sizeof(act));
351	act.sa_handler = (void (*) (int))sig_handler;
352	sigemptyset (&act.sa_mask);
353	act.sa_flags = 0;
354	sigaction(SIGALRM, &act, NULL);
355	sigaction(SIGINT, &act, NULL);
356	sigaction(SIGTERM, &act, NULL);
357
358	/* trigger timeout to prevent hanging processes */
359	alarm(UDEV_ALARM_TIMEOUT);
360
361	sysfs_init();
362	udev_rules_init(&rules, 1);
363
364	udev_scan_class(&device_list);
365	udev_scan_block(&device_list);
366	exec_list(&device_list);
367
368	udev_rules_cleanup(&rules);
369	sysfs_cleanup();
370	selinux_exit();
371	logging_close();
372	return 0;
373}
374